Commit Message

The following patch fixes
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57193
The patch introduces a new heuristic to change order of coloring.
Allocnos conflicting with other allocnos preferring hard registers are
colored first when other higher-level heuristics can not differ them.
On x86_64 this new heuristic results in practically the same SPEC2000
performance and code size.
The patch was successfully bootstrapped and tested on x86-64.
Committed as rev. 257537.